The practice of using steam to re-hydrate hay, or other crop, prior to baling, is discussed in U.S. Pat. Nos. 4,604,857, 4,873,772 and 5,758,479. The acceptance to date of such a harvesting practice has been low, and it is thought that this low acceptance is due to the lack of a fully-integrated machine for producing the steam, treating the crop with steam and processing the treated crop.